Back in 1957, on April Fools Day, the British television program Panorama reported on "a bumper spaghetti harvest" in southern Switzerland. The bountiful crop could be attributed to the mild preceding winter and the disappearance of the nasty spaghetti weevil. After the broadcast, hundreds of people called the BBC, wanting to know how they could grow their own spaghetti trees. The BBC replied, "Place a sprig of spaghetti in a tin of tomato sauce and hope for the best."
If spaghetti can grow on trees, then why can't ukulele strings do the same? In Northern Italy, they've apparently been growing uke strings on "string willows" since at least the 16th century. It all comes down to finding the right balance between sun and rain. That's what ensures that the strings are neither too soft nor too brittle, producing the fine tone that lets Jake Shimabukuro play his uke ever so beautifully.